Fuel Pressure Regulator (Non-Turbo)

Connect a fuel pressure gauge between fuel line and fuel injection manifold. Lift out passenger compartment fuse/relay block. Remove fuel injection main relay. Connect a jumper wire between relay terminals No. 30 & 87/2. See Fig 1 . Fuel pump will run.
Connect a vacuum pump to pressure regulator. Apply vacuum to pressure regulator. Fuel system pressure should drop in direct proportion to amount of vacuum applied to pressure regulator. Replace regulator as necessary.

Fig 1: Identifying Fuel System Relay Locations & Terminals

Courtesy of VOLVO CARS OF NORTH AMERICA.

NOTE: DO NOT increase pressure to pressure regulator more than 10 psi (.70 kg/cm² ).